Flyback transformer devices 70 having coils provided in layers generally comprise, as shown in FIG. 23, a plurality of divided coils 74 wound around a coil bobbin 71, and pairs of terminal pieces 73 provided upright at opposite ends of the bobbin 71. A diode, resistor or like electronic component 6 is connected between each pair of opposed terminal pieces 73, 73.
Each of leads 63, 63 extending from opposite sides of the electronic component 6 is electrically fixedly connected to the terminal piece 73 conventionally by shaping the terminal piece 73 in a Y-form as illustrated, placing the outer end of the lead 63 on the Y-shaped portion of the terminal piece 73, crimping the Y-shaped portion to fix the lead 63 in this state and thereafter soldering the crimped portion by dipping (see, for example, Unexamined Japanese Utility Model Publication HEI 1-105383).
Another method of mounting electronic components on a coil bobbin has been proposed as shown in FIG. 24. A lead 63 is connected to a terminal piece 73a with a solder 66 as shown in FIG. 25 by bending the outer end 63a of the lead 63 to an L-shape, fitting the lead end 63a in a cavity 65 in a post 71a of the coil bobbin at one side of the terminal piece 73a to preliminarily fix the lead 63 as held in contact with the terminal piece 73a and thereafter dipping the fixed portion in solder (Unexamined Japanese Patent Publication SHO 63-15668 and Examined Japanese Utility Model Publication hei 2-1171).
However, the conventional method of mounting electronic components with use of Y-shaped terminal pieces requires the work of fixing the lead by crimping the terminal piece and therefore has the problem of being complex and necessitating cumbersome work.
On the other hand, the method wherein cavities are formed in the coil bobbin not only requires a device for bending leads and a device for inserting the lead into the cavity but also makes the die for producing bobbins complex in configuration to result in an increased cost. Another problem is also encountered in that the coil bobbin becomes larger.
Further when solder dipping is resorted to for connection, the solder dipping device requires labor for maintenance. This leads to an increase in manufacturing cost.